Re: GPL traitor !

From:

Alan Mackenzie

Subject:

Re: GPL traitor !

Date:

Fri, 15 May 2009 10:59:38 +0000 (UTC)

User-agent:

tin/1.6.2-20030910 ("Pabbay") (UNIX) (FreeBSD/4.11-RELEASE (i386))

In gnu.misc.discuss ZnU <address@hidden> wrote:
> In article <address@hidden>, Alan Mackenzie <address@hidden>
> wrote:
>> Eh? What's that got to do with anything? It just means you're free to
>> crack a program restricted by "technological measures" to discern its
>> external data formats and interfaces, so that you can build a compatible
>> program. That's irrelevant for GPL'd programs, since the source code is
>> available, and (by definition) GPL3 programs don't contain such
>> "technological measures". I suppose you might crack a GPL program as a
>> technical exercise, training for cracking close source programs, but so
>> what?
> Hmm.... There's an interesting question here. Let's say you want to
> write a proprietary program that implements the same file format as a
> GPL'd program. Can you really just read the source code to figure out
> that file format, and then go write your app? Or do you have to go
> through a clean-room process, where you have one guy look at the GPL'd
> code and write up a spec, and another guy write the code to implement it?
Depends on what you mean by the verb "implement", I suppose. If the file
format itself is GPL'd (just hold it, Hyman, I know what you're thinking
here without you having to say it), then a proprietary program might not
be legitimate. If we're talking about an "end user" data file, I'd guess
that, on the grounds of interoperability, there wouldn't be any
restrictions. If the file is essentially an internal data structure of
the program, such that there's no question of i14y issues, then it would
be GPL'd, and a proprietary program using it would violate copyright.
I suspect this would be a difficult problem which could go either way in
a court.
I'm not aware of any GPL licensed file formats, though there might well
be some.
--
Alan Mackenzie (Nuremberg, Germany).